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                    5.2020-01-10-性能调优举例一
            
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                    6.2020-01-10-性能调优举例三
            
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                    9.2020-01-15-性能调优举例五
            
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                    3.2019-12-30-dubbo面试
            
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                    1.2019-12-30-性能调优
            
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                    1.2020-01-16-netty入门
            
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                    1.2019-12-28-solr-7.6.0.tgz安装
            
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                    [spring]
            
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                    1.2020-01-12-SpringBoot属性读取方式介绍
            
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                    2.2020-01-12-使用spring boot+mybatis plus快速入门
            
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                    3.2020-01-13-spring-initMethod-destoryMethod
            
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                    4.2020-01-13-spring循环依赖
            
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                    5.2020-01-13-spring源码随记
            
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                    6.2020-01-13-自定义mini-spring
            
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                    [websocket]
            
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                    1.2019-12-30-webscoket-springboot通信
            
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                    [linux]
            
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                    1.2019-12-28-Linux常用命令和快捷键
            
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                    2.2019-12-28-从零到一环境安装
            
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        <li class="chapter " data-level="2.15.3" data-path="../../linux/2019-12-30-vi-常用命令.html">
            
                <a href="../../linux/2019-12-30-vi-常用命令.html">
            
                    
                    3.2019-12-30-vi-常用命令
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.15.4" data-path="../../linux/2019-12-31-awk命令.html">
            
                <a href="../../linux/2019-12-31-awk命令.html">
            
                    
                    4.2019-12-31-awk命令
            
                </a>
            

            
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        <li class="chapter " data-level="2.15.5" data-path="../../linux/2019-12-31-cup信息分析.html">
            
                <a href="../../linux/2019-12-31-cup信息分析.html">
            
                    
                    5.2019-12-31-cup信息分析
            
                </a>
            

            
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        <li class="chapter " data-level="2.15.6" data-path="../../linux/2019-12-31-shell编程.html">
            
                <a href="../../linux/2019-12-31-shell编程.html">
            
                    
                    6.2019-12-31-shell编程
            
                </a>
            

            
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        <li class="chapter " data-level="2.15.7" data-path="../../linux/2019-12-31-top命令.html">
            
                <a href="../../linux/2019-12-31-top命令.html">
            
                    
                    7.2019-12-31-top命令
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.15.8" data-path="../../linux/2019-12-31-普通用户docker的问题.html">
            
                <a href="../../linux/2019-12-31-普通用户docker的问题.html">
            
                    
                    8.2019-12-31-普通用户docker的问题
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.15.9" data-path="../../linux/2020-01-01-centos7 安装kubernetes.html">
            
                <a href="../../linux/2020-01-01-centos7 安装kubernetes.html">
            
                    
                    9.2020-01-01-centos7 安装kubernetes
            
                </a>
            

            
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        <li class="chapter " data-level="2.15.10" data-path="../../linux/2020-01-01-centos安装常用配置.html">
            
                <a href="../../linux/2020-01-01-centos安装常用配置.html">
            
                    
                    10.2020-01-01-centos安装常用配置
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.15.11" data-path="../../linux/2020-01-01-docker使用.html">
            
                <a href="../../linux/2020-01-01-docker使用.html">
            
                    
                    11.2020-01-01-docker使用
            
                </a>
            

            
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        <li class="chapter " data-level="2.15.12" data-path="../../linux/2020-01-01-kubernetes使用.html">
            
                <a href="../../linux/2020-01-01-kubernetes使用.html">
            
                    
                    12.2020-01-01-kubernetes使用
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.15.13" data-path="../../linux/2020-05-12-PG有用的SQL.html">
            
                <a href="../../linux/2020-05-12-PG有用的SQL.html">
            
                    
                    13.2020-05-12-PG有用的SQL
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.15.14" data-path="../../linux/2020-05-12-vim命令.html">
            
                <a href="../../linux/2020-05-12-vim命令.html">
            
                    
                    14.2020-05-12-vim命令
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.16" >
            
                <span>
            
                    
                    [automate]
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.16.1" data-path="../../linux/automate/2020-01-12-redis伪集群创建脚本.html">
            
                <a href="../../linux/automate/2020-01-12-redis伪集群创建脚本.html">
            
                    
                    1.2020-01-12-redis伪集群创建脚本
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.16.2" data-path="../../linux/automate/2020-01-12-tomcat集群创建脚本.html">
            
                <a href="../../linux/automate/2020-01-12-tomcat集群创建脚本.html">
            
                    
                    2.2020-01-12-tomcat集群创建脚本
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.16.3" data-path="../../linux/automate/2020-01-12-zookeeper自动化脚本.html">
            
                <a href="../../linux/automate/2020-01-12-zookeeper自动化脚本.html">
            
                    
                    3.2020-01-12-zookeeper自动化脚本
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.16.4" data-path="../../linux/automate/2020-01-12-其他自动化脚本.html">
            
                <a href="../../linux/automate/2020-01-12-其他自动化脚本.html">
            
                    
                    4.2020-01-12-其他自动化脚本
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.17" >
            
                <span>
            
                    
                    [MySQL]
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.17.1" data-path="../../MySQL/2019-12-31-mysql常用命令.html">
            
                <a href="../../MySQL/2019-12-31-mysql常用命令.html">
            
                    
                    1.2019-12-31-mysql常用命令
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.18" >
            
                <span>
            
                    
                    [nginx]
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.18.1" data-path="../../nginx/2019-12-29-Nginx-Keepalived高可用集群.html">
            
                <a href="../../nginx/2019-12-29-Nginx-Keepalived高可用集群.html">
            
                    
                    1.2019-12-29-Nginx-Keepalived高可用集群
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.18.2" data-path="../../nginx/2020-01-16-nginx参数详细说明.html">
            
                <a href="../../nginx/2020-01-16-nginx参数详细说明.html">
            
                    
                    2.2020-01-16-nginx参数详细说明
            
                </a>
            

            
        </li>
    

            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.19" >
            
                <span>
            
                    
                    [other]
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.19.1" data-path="../../other/2019-12-28-知识小计.html">
            
                <a href="../../other/2019-12-28-知识小计.html">
            
                    
                    1.2019-12-28-知识小计
            
                </a>
            

            
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        <li class="chapter " data-level="2.19.2" data-path="../../other/2020-01-04-科学上网.html">
            
                <a href="../../other/2020-01-04-科学上网.html">
            
                    
                    2.2020-01-04-科学上网
            
                </a>
            

            
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        <li class="chapter " data-level="2.19.3" data-path="../../other/2020-05-13-正则表达式.html">
            
                <a href="../../other/2020-05-13-正则表达式.html">
            
                    
                    3.2020-05-13-正则表达式
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.19.4" data-path="../../other/template.html">
            
                <a href="../../other/template.html">
            
                    
                    4.template
            
                </a>
            

            
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            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.20" >
            
                <span>
            
                    
                    [PostgreSQL]
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.20.1" data-path="../../PostgreSQL/2019-12-28-PostgreSQL安装文档.html">
            
                <a href="../../PostgreSQL/2019-12-28-PostgreSQL安装文档.html">
            
                    
                    1.2019-12-28-PostgreSQL安装文档
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.20.2" data-path="../../PostgreSQL/2019-12-28-Postgres学习笔记.html">
            
                <a href="../../PostgreSQL/2019-12-28-Postgres学习笔记.html">
            
                    
                    2.2019-12-28-Postgres学习笔记
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.20.3" data-path="../../PostgreSQL/2019-12-28-脚本MYSQL导出数据到PG.html">
            
                <a href="../../PostgreSQL/2019-12-28-脚本MYSQL导出数据到PG.html">
            
                    
                    3.2019-12-28-脚本MYSQL导出数据到PG
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.20.4" data-path="../../PostgreSQL/2020-01-04-docker-PostgreSQL安装文档.html">
            
                <a href="../../PostgreSQL/2020-01-04-docker-PostgreSQL安装文档.html">
            
                    
                    4.2020-01-04-docker-PostgreSQL安装文档
            
                </a>
            

            
        </li>
    
        <li class="chapter " data-level="2.20.5" data-path="../../PostgreSQL/2020-01-17-阿里云PG主从切换问题.html">
            
                <a href="../../PostgreSQL/2020-01-17-阿里云PG主从切换问题.html">
            
                    
                    5.2020-01-17-阿里云PG主从切换问题
            
                </a>
            

            
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            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.21" >
            
                <span>
            
                    
                    [python]
            
                </span>
            

            
            <ul class="articles">
                
    
        <li class="chapter " data-level="2.21.1" data-path="../../python/2019-12-28-pip-install指定国内源镜像.html">
            
                <a href="../../python/2019-12-28-pip-install指定国内源镜像.html">
            
                    
                    1.2019-12-28-pip-install指定国内源镜像
            
                </a>
            

            
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        <li class="chapter " data-level="2.21.2" data-path="../../python/2019-12-30-python内置函数.html">
            
                <a href="../../python/2019-12-30-python内置函数.html">
            
                    
                    2.2019-12-30-python内置函数
            
                </a>
            

            
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        <li class="chapter " data-level="2.21.3" data-path="../../python/2019-12-30-一图搞懂基本python语法 .html">
            
                <a href="../../python/2019-12-30-一图搞懂基本python语法 .html">
            
                    
                    3.2019-12-30-一图搞懂基本python语法 
            
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            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.22" >
            
                <span>
            
                    
                    [redis]
            
                </span>
            

            
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        <li class="chapter " data-level="2.22.1" data-path="../../redis/2019-12-28-redis5.0.3安装.html">
            
                <a href="../../redis/2019-12-28-redis5.0.3安装.html">
            
                    
                    1.2019-12-28-redis5.0.3安装
            
                </a>
            

            
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        <li class="chapter " data-level="2.22.2" data-path="../../redis/2019-12-28-redis5.0.3集群搭建.html">
            
                <a href="../../redis/2019-12-28-redis5.0.3集群搭建.html">
            
                    
                    2.2019-12-28-redis5.0.3集群搭建
            
                </a>
            

            
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            </ul>
            
        </li>
    
        <li class="chapter " data-level="2.23" >
            
                <span>
            
                    
                    [tool]
            
                </span>
            

            
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        <li class="chapter " data-level="2.23.1" data-path="../../tool/2019-12-28-idea高效使用技巧和快捷键.html">
            
                <a href="../../tool/2019-12-28-idea高效使用技巧和快捷键.html">
            
                    
                    1.2019-12-28-idea高效使用技巧和快捷键
            
                </a>
            

            
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        <li class="chapter " data-level="2.23.2" data-path="../../tool/2019-12-28-PlantUML画图脚本.html">
            
                <a href="../../tool/2019-12-28-PlantUML画图脚本.html">
            
                    
                    2.2019-12-28-PlantUML画图脚本
            
                </a>
            

            
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        <li class="chapter " data-level="2.23.3" data-path="../../tool/2019-12-30-vscode高效使用.html">
            
                <a href="../../tool/2019-12-30-vscode高效使用.html">
            
                    
                    3.2019-12-30-vscode高效使用
            
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            </ul>
            
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        <li class="chapter " data-level="2.24" >
            
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                    [windows]
            
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        <li class="chapter " data-level="2.24.1" data-path="../../windows/2020-01-12-本地服务成为互联网服务.html">
            
                <a href="../../windows/2020-01-12-本地服务成为互联网服务.html">
            
                    
                    1.2020-01-12-本地服务成为互联网服务
            
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        <li class="chapter " data-level="2.24.2" data-path="../../windows/2020-01-12-注册bat为windows服务.html">
            
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                    2.2020-01-12-注册bat为windows服务
            
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                                <p>ThreadLocal&#x9762;&#x8BD5;&#x516D;&#x8FDE;&#x95EE;&#xFF0C;&#x4F60;&#x80FD;Hold&#x4F4F;&#x5417;&#xFF1F;</p>
<h2 id="&#x573A;&#x666F;&#x73AF;&#x5883;">&#x573A;&#x666F;&#x73AF;&#x5883;</h2>
<p>&#x4E2D;&#x9AD8;&#x7EA7;&#x9636;&#x6BB5;&#x5F00;&#x53D1;&#x8005;&#x51FA;&#x53BB;&#x9762;&#x8BD5;&#xFF0C;&#x5E94;&#x8BE5;&#x8EB2;&#x4E0D;&#x5F00;ThreadLocal&#x76F8;&#x5173;&#x95EE;&#x9898;&#xFF0C;&#x672C;&#x6587;&#x5C31;&#x5E38;&#x89C1;&#x95EE;&#x9898;&#x505A;&#x51FA;&#x4E00;&#x4E9B;&#x89E3;&#x7B54;&#xFF0C;&#x6B22;&#x8FCE;&#x7559;&#x8A00;&#x63A2;&#x8BA8;&#x3002;
ThreadLocal&#x4E3A;Java&#x5E76;&#x53D1;&#x63D0;&#x4F9B;&#x4E86;&#x4E00;&#x4E2A;&#x65B0;&#x7684;&#x601D;&#x8DEF;&#xFF0C; &#x5B83;&#x7528;&#x6765;&#x5B58;&#x50A8;Thread&#x7684;&#x5C40;&#x90E8;&#x53D8;&#x91CF;&#xFF0C; &#x4ECE;&#x800C;&#x8FBE;&#x5230;&#x5404;&#x4E2A;Thread&#x4E4B;&#x95F4;&#x7684;&#x9694;&#x79BB;&#x8FD0;&#x884C;&#x3002;&#x5B83;&#x88AB;&#x5E7F;&#x6CDB;&#x5E94;&#x7528;&#x4E8E;&#x6846;&#x67B6;&#x4E4B;&#x95F4;&#x7684;&#x7528;&#x6237;&#x8D44;&#x6E90;&#x9694;&#x79BB;&#x3001;&#x4E8B;&#x52A1;&#x9694;&#x79BB;&#x7B49;&#x3002;
&#x4F46;&#x662F;&#x7528;&#x4E0D;&#x597D;&#x4F1A;&#x5BFC;&#x81F4;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#xFF0C; &#x672C;&#x6587;&#x91CD;&#x70B9;&#x7528;&#x4E8E;&#x5BF9;&#x5B83;&#x7684;&#x4F7F;&#x7528;&#x8FC7;&#x7A0B;&#x7684;&#x7591;&#x96BE;&#x89E3;&#x7B54;&#xFF0C; &#x76F8;&#x4FE1;&#x4ED4;&#x7EC6;&#x9605;&#x8BFB;&#x5B8C;&#x540E;&#x7684;&#x670B;&#x53CB;&#x53EF;&#x4EE5;&#x968F;&#x5FC3;&#x6240;&#x6B32;&#x7684;&#x5B89;&#x5168;&#x4F7F;&#x7528;&#x5B83;&#x3002;</p>
<h2 id="&#x4E00;&#x3001;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x539F;&#x56E0;&#x63A2;&#x7D22;">&#x4E00;&#x3001;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x539F;&#x56E0;&#x63A2;&#x7D22;</h2>
<p>ThreadLocal&#x64CD;&#x4F5C;&#x4E0D;&#x5F53;&#x4F1A;&#x5F15;&#x53D1;&#x5185;&#x5B58;&#x6CC4;&#x9732;&#xFF0C;&#x6700;&#x4E3B;&#x8981;&#x7684;&#x539F;&#x56E0;&#x5728;&#x4E8E;&#x5B83;&#x7684;&#x5185;&#x90E8;&#x7C7B;ThreadLocalMap&#x4E2D;&#x7684;Entry&#x7684;&#x8BBE;&#x8BA1;&#x3002;
Entry&#x7EE7;&#x627F;&#x4E86;WeakReference<threadlocal<?>&gt;&#xFF0C;&#x5373;Entry&#x7684;key&#x662F;&#x5F31;&#x5F15;&#x7528;&#xFF0C;&#x6240;&#x4EE5;key&apos;&#x4F1A;&#x5728;&#x5783;&#x573E;&#x56DE;&#x6536;&#x7684;&#x65F6;&#x5019;&#x88AB;&#x56DE;&#x6536;&#x6389;&#xFF0C; &#x800C;key&#x5BF9;&#x5E94;&#x7684;value&#x5219;&#x4E0D;&#x4F1A;&#x88AB;&#x56DE;&#x6536;&#xFF0C; &#x8FD9;&#x6837;&#x4F1A;&#x5BFC;&#x81F4;&#x4E00;&#x79CD;&#x73B0;&#x8C61;&#xFF1A;key&#x4E3A;null&#xFF0C;value&#x6709;&#x503C;&#x3002;
key&#x4E3A;&#x7A7A;&#x7684;&#x8BDD;value&#x662F;&#x65E0;&#x6548;&#x6570;&#x636E;&#xFF0C;&#x4E45;&#x800C;&#x4E45;&#x4E4B;&#xFF0C;value&#x7D2F;&#x52A0;&#x5C31;&#x4F1A;&#x5BFC;&#x81F4;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x3002;</threadlocal<?></p>
<h2 id="&#x4E8C;&#x3001;&#x600E;&#x4E48;&#x89E3;&#x51B3;&#x8FD9;&#x4E2A;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x95EE;&#x9898;">&#x4E8C;&#x3001;&#x600E;&#x4E48;&#x89E3;&#x51B3;&#x8FD9;&#x4E2A;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x95EE;&#x9898;</h2>
<p>&#x6BCF;&#x6B21;&#x4F7F;&#x7528;&#x5B8C;ThreadLocal&#x90FD;&#x8C03;&#x7528;&#x5B83;&#x7684;remove()&#x65B9;&#x6CD5;&#x6E05;&#x9664;&#x6570;&#x636E;&#x3002;&#x56E0;&#x4E3A;&#x5B83;&#x7684;remove&#x65B9;&#x6CD5;&#x4F1A;&#x4E3B;&#x52A8;&#x5C06;&#x5F53;&#x524D;&#x7684;key&#x548C;value(Entry)&#x8FDB;&#x884C;&#x6E05;&#x9664;&#x3002;</p>
<p>e.clear()&#x7528;&#x4E8E;&#x6E05;&#x9664;Entry&#x7684;key&#xFF0C;&#x5B83;&#x8C03;&#x7528;&#x7684;&#x662F;WeakReference&#x4E2D;&#x7684;&#x65B9;&#x6CD5;:this.referent = null
expungeStaleEntry(i)&#x7528;&#x4E8E;&#x6E05;&#x9664;Entry&#x5BF9;&#x5E94;&#x7684;value&#xFF0C; &#x8FD9;&#x4E2A;&#x540E;&#x9762;&#x4F1A;&#x8BE6;&#x7EC6;&#x8BB2;&#x3002;</p>
<h2 id="&#x4E09;&#x3001;jdk&#x5F00;&#x53D1;&#x8005;&#x662F;&#x5982;&#x4F55;&#x907F;&#x514D;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x7684;">&#x4E09;&#x3001;JDK&#x5F00;&#x53D1;&#x8005;&#x662F;&#x5982;&#x4F55;&#x907F;&#x514D;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x7684;</h2>
<p>ThreadLocal&#x7684;&#x8BBE;&#x8BA1;&#x8005;&#x4E5F;&#x610F;&#x8BC6;&#x5230;&#x4E86;&#x8FD9;&#x4E00;&#x70B9;(&#x5185;&#x5B58;&#x6CC4;&#x6F0F;)&#xFF0C; &#x4ED6;&#x4EEC;&#x5728;&#x4E00;&#x4E9B;&#x65B9;&#x6CD5;&#x4E2D;&#x57CB;&#x4E86;&#x5BF9;key=null&#x7684;value&#x64E6;&#x9664;&#x64CD;&#x4F5C;&#x3002;
&#x8FD9;&#x91CC;&#x62FF;ThreadLocal&#x63D0;&#x4F9B;&#x7684;get()&#x65B9;&#x6CD5;&#x4E3E;&#x4F8B;&#xFF0C;&#x5B83;&#x8C03;&#x7528;&#x4E86;ThreadLocalMap#getEntry()&#x65B9;&#x6CD5;&#xFF0C;&#x5BF9;key&#x8FDB;&#x884C;&#x4E86;&#x6821;&#x9A8C;&#x548C;&#x5BF9;null key&#x8FDB;&#x884C;&#x64E6;&#x9664;&#x3002;</p>
<p>&#x5982;&#x679C;key&#x4E3A;null&#xFF0C; &#x5219;&#x4F1A;&#x8C03;&#x7528;getEntryAfterMiss()&#x65B9;&#x6CD5;&#xFF0C;&#x5728;&#x8FD9;&#x4E2A;&#x65B9;&#x6CD5;&#x4E2D;&#xFF0C;&#x5982;&#x679C;k == null &#xFF0C; &#x5219;&#x8C03;&#x7528;expungeStaleEntry(i);&#x65B9;&#x6CD5;&#x3002;
expungeStaleEntry(i)&#x65B9;&#x6CD5;&#x5B8C;&#x6210;&#x4E86;&#x5BF9;key=null &#x7684;key&#x6240;&#x5BF9;&#x5E94;&#x7684;value&#x8FDB;&#x884C;&#x8D4B;&#x7A7A;&#xFF0C; &#x91CA;&#x653E;&#x4E86;&#x7A7A;&#x95F4;&#x907F;&#x514D;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x3002;
&#x540C;&#x65F6;&#x5B83;&#x904D;&#x5386;&#x4E0B;&#x4E00;&#x4E2A;key&#x4E3A;&#x7A7A;&#x7684;entry&#xFF0C; &#x5E76;&#x5C06;value&#x8D4B;&#x503C;&#x4E3A;null&#xFF0C; &#x7B49;&#x5F85;&#x4E0B;&#x6B21;GC&#x91CA;&#x653E;&#x6389;&#x5176;&#x7A7A;&#x95F4;&#x3002;</p>
<p>&#x540C;&#x7406;&#xFF0C; set()&#x65B9;&#x6CD5;&#x6700;&#x7EC8;&#x4E5F;&#x662F;&#x8C03;&#x7528;&#x8BE5;&#x65B9;&#x6CD5;(expungeStaleEntry)&#xFF0C; &#x8C03;&#x7528;&#x8DEF;&#x5F84;: 
set(T value)-&gt;
map.set(this, value)-&gt;
rehash()-&gt;
expungeStaleEntries()
remove&#x65B9;&#x6CD5;
remove()-&gt;
ThreadLocalMap.remove(this)-&gt;
expungeStaleEntry(i)
&#x8FD9;&#x6837;&#x505A;&#xFF0C; &#x4E5F;&#x53EA;&#x80FD;&#x8BF4;&#x5C3D;&#x53EF;&#x80FD;&#x907F;&#x514D;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#xFF0C; &#x4F46;&#x5E76;&#x4E0D;&#x4F1A;&#x5B8C;&#x5168;&#x89E3;&#x51B3;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#x8FD9;&#x4E2A;&#x95EE;&#x9898;&#x3002;&#x6BD4;&#x5982;&#x6781;&#x7AEF;&#x60C5;&#x51B5;&#x4E0B;&#x6211;&#x4EEC;&#x53EA;&#x521B;&#x5EFA;ThreadLocal&#x4F46;&#x4E0D;&#x8C03;&#x7528;set&#x3001;get&#x3001;remove&#x65B9;&#x6CD5;&#x7B49;&#x3002;&#x6240;&#x4EE5;&#x6700;&#x80FD;&#x89E3;&#x51B3;&#x95EE;&#x9898;&#x7684;&#x529E;&#x6CD5;&#x5C31;&#x662F;&#x7528;&#x5B8C;ThreadLocal&#x540E;&#x624B;&#x52A8;&#x8C03;&#x7528;remove().</p>
<h2 id="&#x56DB;&#x3001;&#x624B;&#x52A8;&#x91CA;&#x653E;threadlocal&#x9057;&#x7559;&#x5B58;&#x50A8;&#x4F60;&#x600E;&#x4E48;&#x53BB;&#x8BBE;&#x8BA1;&#x5B9E;&#x73B0;&#xFF1F;">&#x56DB;&#x3001;&#x624B;&#x52A8;&#x91CA;&#x653E;ThreadLocal&#x9057;&#x7559;&#x5B58;&#x50A8;?&#x4F60;&#x600E;&#x4E48;&#x53BB;&#x8BBE;&#x8BA1;/&#x5B9E;&#x73B0;&#xFF1F;</h2>
<p>&#x8FD9;&#x91CC;&#x4E3B;&#x8981;&#x662F;&#x5F3A;&#x5316;&#x4E00;&#x4E0B;&#x624B;&#x52A8;remove&#x7684;&#x601D;&#x60F3;&#x548C;&#x5FC5;&#x8981;&#x6027;&#xFF0C;&#x8BBE;&#x8BA1;&#x601D;&#x60F3;&#x4E0E;&#x8FDE;&#x63A5;&#x6C60;&#x7C7B;&#x4F3C;&#x3002;
&#x5305;&#x88C5;&#x5176;&#x7236;&#x7C7B;remove&#x65B9;&#x6CD5;&#x4E3A;&#x9759;&#x6001;&#x65B9;&#x6CD5;&#xFF0C;&#x5982;&#x679C;&#x662F;spring&#x9879;&#x76EE;&#xFF0C; &#x53EF;&#x4EE5;&#x501F;&#x52A9;&#x4E8E;bean&#x7684;&#x58F0;&#x660E;&#x5468;&#x671F;&#xFF0C; &#x5728;&#x62E6;&#x622A;&#x5668;&#x7684;afterCompletion&#x9636;&#x6BB5;&#x8FDB;&#x884C;&#x8C03;&#x7528;&#x3002;
&#x5F31;&#x5F15;&#x7528;&#x5BFC;&#x81F4;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#xFF0C;&#x90A3;&#x4E3A;&#x4EC0;&#x4E48;key&#x4E0D;&#x8BBE;&#x7F6E;&#x4E3A;&#x5F3A;&#x5F15;&#x7528;
&#x8FD9;&#x4E2A;&#x95EE;&#x9898;&#x5C31;&#x6BD4;&#x8F83;&#x6709;&#x6DF1;&#x5EA6;&#x4E86;&#xFF0C;&#x662F;&#x4F60;&#x8C08;&#x85AA;&#x7684;&#x5C0F;&#x5C0F;&#x8D44;&#x672C;&#x3002;
&#x5982;&#x679C;key&#x8BBE;&#x7F6E;&#x4E3A;&#x5F3A;&#x5F15;&#x7528;&#xFF0C; &#x5F53;threadLocal&#x5B9E;&#x4F8B;&#x91CA;&#x653E;&#x540E;&#xFF0C; threadLocal=null&#xFF0C; &#x4F46;&#x662F;threadLocal&#x4F1A;&#x6709;&#x5F3A;&#x5F15;&#x7528;&#x6307;&#x5411;threadLocalMap&#xFF0C;threadLocalMap.Entry&#x53C8;&#x5F3A;&#x5F15;&#x7528;threadLocal&#xFF0C; &#x8FD9;&#x6837;&#x4F1A;&#x5BFC;&#x81F4;threadLocal&#x4E0D;&#x80FD;&#x6B63;&#x5E38;&#x88AB;GC&#x56DE;&#x6536;&#x3002;
&#x5F31;&#x5F15;&#x7528;&#x867D;&#x7136;&#x4F1A;&#x5F15;&#x8D77;&#x5185;&#x5B58;&#x6CC4;&#x6F0F;&#xFF0C; &#x4F46;&#x662F;&#x4E5F;&#x6709;set&#x3001;get&#x3001;remove&#x65B9;&#x6CD5;&#x64CD;&#x4F5C;&#x5BF9;null key&#x8FDB;&#x884C;&#x64E6;&#x9664;&#x7684;&#x8865;&#x6551;&#x63AA;&#x65BD;&#xFF0C; &#x65B9;&#x6848;&#x4E0A;&#x7565;&#x80DC;&#x4E00;&#x7B79;&#x3002;
&#x7EBF;&#x7A0B;&#x6267;&#x884C;&#x7ED3;&#x675F;&#x540E;&#x4F1A;&#x4E0D;&#x4F1A;&#x81EA;&#x52A8;&#x6E05;&#x7A7A;Entry&#x7684;value
&#x4E00;&#x5E76;&#x8003;&#x5BDF;&#x4E86;&#x4F60;&#x7684;gc&#x57FA;&#x7840;&#x3002;
&#x4E8B;&#x5B9E;&#x4E0A;&#xFF0C;&#x5F53;currentThread&#x6267;&#x884C;&#x7ED3;&#x675F;&#x540E;&#xFF0C; threadLocalMap&#x53D8;&#x5F97;&#x4E0D;&#x53EF;&#x8FBE;&#x4ECE;&#x800C;&#x88AB;&#x56DE;&#x6536;&#xFF0C;Entry&#x7B49;&#x4E5F;&#x5C31;&#x90FD;&#x88AB;&#x56DE;&#x6536;&#x4E86;&#xFF0C;&#x4F46;&#x8FD9;&#x4E2A;&#x73AF;&#x5883;&#x5C31;&#x8981;&#x6C42;&#x4E0D;&#x5BF9;Thread&#x8FDB;&#x884C;&#x590D;&#x7528;&#xFF0C;&#x4F46;&#x662F;&#x6211;&#x4EEC;&#x9879;&#x76EE;&#x4E2D;&#x7ECF;&#x5E38;&#x4F1A;&#x590D;&#x7528;&#x7EBF;&#x7A0B;&#x6765;&#x63D0;&#x9AD8;&#x6027;&#x80FD;&#xFF0C; &#x6240;&#x4EE5;currentThread&#x4E00;&#x822C;&#x4E0D;&#x4F1A;&#x5904;&#x4E8E;&#x7EC8;&#x6B62;&#x72B6;&#x6001;&#x3002;</p>
<h2 id="&#x4E94;&#x3001;thread&#x548C;threadlocal&#x6709;&#x4EC0;&#x4E48;&#x8054;&#x7CFB;&#x5462;">&#x4E94;&#x3001;Thread&#x548C;ThreadLocal&#x6709;&#x4EC0;&#x4E48;&#x8054;&#x7CFB;&#x5462;</h2>
<p>ThreadLocal&#x7684;&#x6982;&#x5FF5;&#x3002;
Thread&#x548C;ThreadLocal&#x662F;&#x7ED1;&#x5B9A;&#x7684;&#xFF0C; ThreadLocal&#x4F9D;&#x8D56;&#x4E8E;Thread&#x53BB;&#x6267;&#x884C;&#xFF0C; Thread&#x5C06;&#x9700;&#x8981;&#x9694;&#x79BB;&#x7684;&#x6570;&#x636E;&#x5B58;&#x653E;&#x5230;ThreadLocal(&#x51C6;&#x786E;&#x7684;&#x8BB2;&#x662F;ThreadLocalMap)&#x4E2D;, &#x6765;&#x5B9E;&#x73B0;&#x591A;&#x7EBF;&#x7A0B;&#x5904;&#x7406;&#x3002;
&#x76F8;&#x5173;&#x95EE;&#x9898;&#x6269;&#x5C55;
&#x52A0;&#x5206;&#x9879;&#x6765;&#x4E86;&#x3002;</p>
<h2 id="&#x516D;&#x3001;spring&#x5982;&#x4F55;&#x5904;&#x7406;bean&#x591A;&#x7EBF;&#x7A0B;&#x4E0B;&#x7684;&#x5E76;&#x53D1;&#x95EE;&#x9898;">&#x516D;&#x3001;Spring&#x5982;&#x4F55;&#x5904;&#x7406;Bean&#x591A;&#x7EBF;&#x7A0B;&#x4E0B;&#x7684;&#x5E76;&#x53D1;&#x95EE;&#x9898;</h2>
<p>ThreadLocal&#x5929;&#x751F;&#x4E3A;&#x89E3;&#x51B3;&#x76F8;&#x540C;&#x53D8;&#x91CF;&#x7684;&#x8BBF;&#x95EE;&#x51B2;&#x7A81;&#x95EE;&#x9898;&#xFF0C; &#x6240;&#x4EE5;&#x8FD9;&#x4E2A;&#x5BF9;&#x4E8E;spring&#x7684;&#x9ED8;&#x8BA4;&#x5355;&#x4F8B;bean&#x7684;&#x591A;&#x7EBF;&#x7A0B;&#x8BBF;&#x95EE;&#x662F;&#x4E00;&#x4E2A;&#x5B8C;&#x7F8E;&#x7684;&#x89E3;&#x51B3;&#x65B9;&#x6848;&#x3002;spring&#x4E5F;&#x786E;&#x5B9E;&#x662F;&#x7528;&#x4E86;ThreadLocal&#x6765;&#x5904;&#x7406;&#x591A;&#x7EBF;&#x7A0B;&#x4E0B;&#x76F8;&#x540C;&#x53D8;&#x91CF;&#x5E76;&#x53D1;&#x7684;&#x7EBF;&#x7A0B;&#x5B89;&#x5168;&#x95EE;&#x9898;&#x3002;
spring &#x5982;&#x4F55;&#x4FDD;&#x8BC1;&#x6570;&#x636E;&#x5E93;&#x4E8B;&#x52A1;&#x5728;&#x540C;&#x4E00;&#x4E2A;&#x8FDE;&#x63A5;&#x4E0B;&#x6267;&#x884C;&#x7684;
&#x8981;&#x60F3;&#x5B9E;&#x73B0;jdbc&#x4E8B;&#x52A1;&#xFF0C; &#x5C31;&#x5FC5;&#x987B;&#x662F;&#x5728;&#x540C;&#x4E00;&#x4E2A;&#x8FDE;&#x63A5;&#x5BF9;&#x8C61;&#x4E2D;&#x64CD;&#x4F5C;&#xFF0C; &#x591A;&#x4E2A;&#x8FDE;&#x63A5;&#x4E0B;&#x4E8B;&#x52A1;&#x5C31;&#x4F1A;&#x4E0D;&#x53EF;&#x63A7;&#xFF0C; &#x9700;&#x8981;&#x501F;&#x52A9;&#x5206;&#x5E03;&#x5F0F;&#x4E8B;&#x52A1;&#x5B8C;&#x6210;&#x3002;&#x90A3;spring &#x5982;&#x4F55;&#x4FDD;&#x8BC1;&#x6570;&#x636E;&#x5E93;&#x4E8B;&#x52A1;&#x5728;&#x540C;&#x4E00;&#x4E2A;&#x8FDE;&#x63A5;&#x4E0B;&#x6267;&#x884C;&#x7684;&#x5462;&#xFF1F;
DataSourceTransactionManager &#x662F;spring&#x7684;&#x6570;&#x636E;&#x6E90;&#x4E8B;&#x52A1;&#x7BA1;&#x7406;&#x5668;&#xFF0C; &#x5B83;&#x4F1A;&#x5728;&#x4F60;&#x8C03;&#x7528;getConnection()&#x7684;&#x65F6;&#x5019;&#x4ECE;&#x6570;&#x636E;&#x5E93;&#x8FDE;&#x63A5;&#x6C60;&#x4E2D;&#x83B7;&#x53D6;&#x4E00;&#x4E2A;connection&#xFF0C; &#x7136;&#x540E;&#x5C06;&#x5176;&#x4E0E;ThreadLocal&#x7ED1;&#x5B9A;&#xFF0C; &#x4E8B;&#x52A1;&#x5B8C;&#x6210;&#x540E;&#x89E3;&#x9664;&#x7ED1;&#x5B9A;&#x3002;&#x8FD9;&#x6837;&#x5C31;&#x4FDD;&#x8BC1;&#x4E86;&#x4E8B;&#x52A1;&#x5728;&#x540C;&#x4E00;&#x8FDE;&#x63A5;&#x4E0B;&#x5B8C;&#x6210;&#x3002;
&#x6982;&#x8981;&#x6E90;&#x7801;&#xFF1A;</p>
<ol>
<li>&#x4E8B;&#x52A1;&#x5F00;&#x59CB;&#x9636;&#x6BB5;&#xFF1A;
org.springframework.jdbc.datasource.DataSourceTransactionManager#doBegin-&gt;TransactionSynchronizationManager#bindResource-&gt;org.springframework.transaction.support.TransactionSynchronizationManager#bindResource</li>
<li>&#x4E8B;&#x52A1;&#x7ED3;&#x675F;&#x9636;&#x6BB5;:
org.springframework.jdbc.datasource.DataSourceTransactionManager#doCleanupAfterCompletion-&gt;TransactionSynchronizationManager#unbindResource-&gt;org.springframework.transaction.support.TransactionSynchronizationManager#unbindResource-&gt;TransactionSynchronizationManager#doUnbindResource</li>
</ol>

                                
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